Introduction: Model Safe - Hidden in Plain Sight

About: I have a lifetime of working on things. Jack of all trades, master of none.

Here is a new take on an old theme of hiding valuables in plain sight where others might not think to look. Some people hide money in a mattress, some in a drawer and some in a jar. Others hide it in a bible, an envelope or in their car.

Recently I designed a couple of 3D printed models; a 50's Willys Wagon & a Biplane. In honor of the “Safe + Secure” challenge I decided to cut apart one of my model designs and remake it into a “safe” for my Daughter’s birthday. This is a fully printed design that was made to look like a model Willys Wagon so that valuables can hide in plain sight. Not only is this an original design, but it is the first time I enlisted my daughter’s help for video and photographic assistance. She is 14 years old so I am still waiting for some of the results to come in. When they do I will add them.

I did the design work in Tinkercad and everything is my own concept except for the tires and the rear accessory pack of jerry can (ossum-Thingiverse), bracket (robward-Thingiverse), and fire extinguisher (IonNight-Thingiverse). Although I did need to alter each of these to fit my scale and needs.


PLA filament for my Dremel Printer

Acrylic paints


Spray paint

Table salt for the paint method I used

5 minute epoxy or super glue

Safety Warning:

Paint and glue in well ventilated areas. If appropriate use a respirator and gloves.

I personally use a flush-cut Weller wire cutter versus a hobby knife to clean up my prints so that I don’t cut myself when cleaning prints.

Step 1: Design and Print

The design work for this project was mostly done already as I had previously designed, printed, glued and painted a model version. So I only had to slice it apart and add a threaded post to hold it all together. I cut up the Willy’s body to create a cavity and used the existing model parts from the previous build. I am not going to show how you how to design in CAD. I use Tinkercad and I have been practicing for a few years now. I still have much to learn, but I am getting better all the time. I then created a name plate and painted the same color as the body so that it appears to be glued on and is not obviously the head of a screw.

I put a short video showing the shapes that make up the body of the Willys. This video does not show the order of the design, but rather the pieces that make up the design.

I printed the body parts and the accessory parts separately. I would recommend that you print the threaded post in a high quality print with a lot of infill as it has a fair amount of stress applied and you wouldn’t want it to snap off rendering the safe feature unusable. All of the model’s accessory parts are printed in one print. This is a lot of individual parts for one print, but it works out well.

My design prints fine without supports in the rear wheel wells, but probably would print better if supports were added. I did add support to the front window area as I had to print cab down to create the inner cavity, and I did not wish to have to try to remove supports from inside of the body. My hands are just too large for that and the remnants would catch the tray as it slides in and out.

Step 2: Paint and Assemble

I painted most of the parts before gluing them to the body. The exception is that the front fenders get attached before painting. I used a technique for painting the body that I learned here on Instructables. That is that I used three colors of spray paint: Sage, Green, and Black and I let some of the colors show through by applying salt that is then over sprayed with a lighter color. When the salt is rubbed off it exposes the undercoats as if it was a failing paint job of an old vehicle. I used this method on my Snake in the Box build too. The painting procedure is shown in Step 6 of that Instructable. //

The rest of the parts are hand painted with Acrylic paints. Acrylic covers well and is easy to clean up with water after use.

I hope to add a video later that will show the location of the parts and how to assemble them. It does not show the fenders being glued onto the body or the inner sliding tray being glued to the back plate. We have video of the assembly already, but I waiting to see if my daughter can bring it together in an edited format.

I use a very fast curing super glue for my PLA parts and it seems to work out very well. The glue is from Hobby Town USA and the part number is IC-2000. It is a carbon & rubber toughened super glue.

Step 3: Place Valuables Inside and Display

I am very satisfied with the results. I doubt that my wife will wish it to sit in our living room as a display piece, but it is nice enough that she will not care if it is on the shelf in our office or in one of the kid’s bedrooms.

There is a video of the opening of the Safe in this Step.

Step 4: Conclusion

I had a blast making this model and painting it. I feel that it is a close enough effort of copying a Willys Wagon though not good enough to gather too much attention. I made the name plate as inconspicuous as I could, but if someone picks up the model the rattle of the goods inside will give the intended purpose away.

If you wish to make one of your own Here are a couple of links to get the files off of Tinkercad:

First for the body parts:

Second link includes the accessory components:

These links are in case the attached files do not work for you. Unfortunately my computer turns stl files into Dremel stl files which I understand can not be opened by all.

Bonus: I have an extra proto-type model printed out and I will be willing to send it to someone who reads this Instructable. If you are interested in winning a version of the model without the inner “safe” feature, please leave a comment below and include an interest in being entered to win the already 3D printed though unpainted and unassembled model. This one is just like my original model with some improvements to the body and it is ready for paint and assembly. When winners of the Safe + Secure contest are announced I will have a drawing of those who expressed an interest and let you know if you are the winner.

Questions and comments always welcome.

Thank you,


Safe and Secure Challenge

Runner Up in the
Safe and Secure Challenge